\documentclass[11pt]{article}

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$1-8/a$
$$444$$
$$1$$$$2$$$3$
$$formula1$$$$formula2$$$formula3$$$formula4$$

NB! Doesn't check illegal synt., i.e. ££a£ and £a££ (where £ represents the dollar sign), nor £a££b£ (the .tex file won't compile, so no need?)

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